题目内容

You ______swim in this part of the lake. It’s dangerous.

A．mustn’t

B．needn’t

C．won’t

D．may

 

【答案】

A

【解析】略

 

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—You___________ stop me.

   —Even if you __________it, I won't allow you to swim across the river.

A. mustn’t; dare not do            B. may; dare not do  

C. can; dare to do                  D. needn't; dare do

The surprising experiment I am about to describe proves that air is all around you and that it proves down upon you. Air pressure is a wonderful force. When you swim underwater, you can feel water push down your body. The air all around you does the same. However, your body is so used to it that you do not notice this. The pressure is caused by a layer of air called the atmosphere. This layer surrounds the Earth, extending to about five kilometers above the Earth’s surface.

The following experiment is an easy one that you can do at home. But make sure that you are supervised, because you will need to use matches. Now foe the experiment！

    What you need

    ·A hard-boiled egg without the shell

    ·A bottle with a neck slightly smaller than the egg

·A piece of paper

·A match

Metheod

1） Check that the paper will sit firmly on the neck of the bottle.

2） Tear the paper into strips and put the strips into the bottle.

3） Light the paper by dropping a burning match into the bottle.

4） Quickly sit the egg on the neck of the bottle.

Result

  Astonishingly, the egg will be sucked into the bottle. Your friends will be amazed when you show them the experiment. But be careful when you handle matches.

Why it happened

As the paper burns, it needs oxygen and uses up the oxygen （air） in the bottle. The egg acts as a seal in the neck of the bottle, so no more air can get inside. This reduces the air pressure inside the bottle. The air pressure must equalize, so more air from outside must enter the bottle. The outside air pressure against the egg and then the egg is pushed into the bottle! The proves that air is all around and that it is pressing down on it.

64．Why is there the need to take care when you are doing the experiment?

       A．The bottle could break.

       B．You need to light the paper with a match.

       C．The egg needs to be shelled.

       D．The egg has to be perfectly placed on the neck of the bottle.

65．In the experiment, the burning inside the bottle can___.

       A．equalize the air pressure inside and outside

       B．make a seal in the neck of the bottle

       C．finish up the oxygen inside the bottle

       D．produce more oxygen inside the bottle

66．How did the egg put into the bottle？

       A．The oxygen inside the bottle sucked the egg in.

       B．It became salt without the shell.

       C．The neck of the bottle was wide enough.

       D．The outside air pressure forced it into the bottle.

67．The experiment is carried cut to prove ______.

       A．water pushes on your body when you swim underwater.

       B．the earth is surrounded by a layer of air called the atmosphere.

       C．the pressure of air around us has a powerful force.

       D．the air pressure is not equalized around us.

Jimmy lives in London and began swimming a few months ago.

  He likes swimming, and often goes to the swimming pool near by his_____

  house with his mother and swims there for a hour or so.           ______

  He was six year old last week, and his mother said, “You          ______

  swim quite good now, but you have never seen the sea, my         _____

  child, haven’t you? Your father and I are going to take you         _____

  there on Saturday, and you are going to swimming in the sea.       _______

  It isn’t cold now, and it’s much nice than a swimming pool.”        _____

  Jimmy’s father and mother brought him to the sea in their          _______

  car on Saturday, but they stopped at the side of a small            ________

  harbor(港口). Jimmy got out and looked at the sea for long        ______

  time, but wasn’t happy. Then he said to his mother,

   “Which is the shallow end, mother?”.

The surprising experiment I am about to describe proves that air is all aroud you and that it proves down upon you．Air pressure is a wonderful force．When you swim underwater, you can feel water push down your body．The air all around you does the same．However, your body is so used to it that you do not notice this ．The pressure is caused by a layer of air called the atmosphere．This layer surrounds the Earth , extending to about five kilometers above the Earth’s surface．

The following experiment is an easy one that you can do at home．But make sure that you are supervised , because you will need to use matches．Now for the experiment！

What you need

·A hard-boiled egg without the shell

·A bottle with a neck slightly smaller than the egg

·A piece of paper

·A match

Metheod

1) Check that the egg will sit firmly on the neck of the bottle．

2) Tear the paper into strips and put the strips into the bottle．

3) Light the paper by dropping a burning match into the bottle．

4) Quickly sit the egg on the neck of the bottle．

Result

Astonishingly,the egg will be sucked into the bottle．Your friends will be amazed when you show them the experiment．But be careful when you handle matches．

Why it happened

As the paper burns,it needs oxyen and uses up the oxygen(air) in the bottle．The egg acts as a seal in the neck of the bottle,so no more air can get inside ．This reduces the air pressure inside the bottle．The air pressure must equalize,so more air from outside must enter the bottle．The outside air pressure against the egg and then the egg is pushed into the bottle!The proves that air is all around and that it is pressing down on it．

1．When you do the experiment, why need you a person beside you?

     A．You couldn’t place the egg on the bottle by yourself．

     B．The egg needs to be shelled．

     C．You need to use matches．

     D．The bottle can’t sit firmly on the desk．

2．The purpose of doing this experiment is to prove ______．

     A．air pressure is a wonderful force

     B．water can push down your body when you swim underwater

     C．the air pressure is not equalized around us

     D．the earth is surrounded by a layer of air called the atmosphere

3．How did the egg put into the bottle？

       A．The oxygen inside the bottle suckde the egg in．

       B．It became solt without the shell．

       C．The neck of the bottle was wide enough．

       D．The outside air pressure forced it into the bottle．

4．The passage is ______．

     A．an experiment report           B．a scientific story

     C．a research report                  D．an interesting novel

One day a rabbit ran into an elephant. "Hello," said the rabbit. "Fine day, isn’t it?" The elephant stopped to look down at the tiny(小的) creature and shouted. "Leave me alone. I don’t have the time to waste on someone so small." The rabbit was shocked by the elephant’s words. Then he decided to ask the whale(鲸鱼) what she thought about the elephant’s rudeness. But the whale laughed at this tiny animal. The rabbit said, "You think that I am weak, but in fact, I am strong! I can beat you at Tug-of-War (拔河比赛)."The whale looked at him for a moment before bursting into laughter. "Very well, little one. Go and get a rope," she said.The rabbit ran off to find a strong and thick rope. Then he went to the elephant, "Elephant, I will beat you at a game of Tug-of-War." The elephant laughed loudly, but agreed to challenge the tiny animal. He tied the rope around his huge waist. The rabbit took the other end and ran away. He called back to the elephant, "When I say 'pull’, you start pulling. "The rabbit took the other end of the rope to the whale, "Tie this to your tail and when I say 'pull’，you swim." The whale tied the rope to her tail after laughing at the rabbit’s foolishness. Then the rabbit called out "PULL!" The elephant and the whale began pulling. After a while, they were too tired to continue. The elephant and the whale never knew how such a tiny creature could beat them. But from that day on, they said "hello" to the little rabbit with great respect whenever they met.
【小题1】Why did the rabbit want a game of Tug-of-War?
　  

A．He wanted to show he was the best.
B．He knew that he could do well in this game.
　		C．He wanted to get respect from the elephant and the whale.
D．He wanted to prove he wasn’t the tiniest animal.
【小题2】What do you think of the rabbit according to the story?
  
A．Smart and brave.B．Tiny and stupid.
C．Pride and naughty.D．Poor and weak.
【小题3】Why did the elephant and the whale lose the game?
A．They didn’t prepare for it.
B．They were not as strong as the rabbit.
C．They were too impolite to the little rabbit.
D．They actually fought with each other but not the rabbit.
【小题4】Which statement is TRUE according to the passage?
A．The elephant was pleased to talk to the rabbit at first.
B．It was the whale who suggested having a game of Tug-of-War.
C．The rabbit was stronger than both the whale and the elephant.
D．The whale and the elephant began to respect the rabbit from then on.

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